替代3' UTRs作为支架来调节膜蛋白局部化的作用
Binyamin D Berkovits1, Christine Mayr1
1Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, 1275 York Ave, New York, New York 10065, USA.
Nature
|April 22, 2015
概括
替代多基化 (ApA) 生成不同的3'未翻译区域 (3' UTRs),控制膜蛋白的定位和功能. 这种机制扩大了蛋白质组的多样性,而不改变蛋白质序列,影响细胞表面表达.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 是一个遗传学.
背景情况:
- 替代裂变和多化 (ApA) 影响大约一半的人类基因,产生不同3'未翻译区域 (3' UTR) 长度的mRNA转录.
- 这些3' UTRs可以影响蛋白质的功能和定位,即使蛋白质序列保持不变.
研究的目的:
- 调查替代3' UTRs如何调节膜蛋白的翻译后定位和功能.
- 阐明3' UTRs调解蛋白贩运的分子机制.
主要方法:
- 利用人类细胞系研究替代3' UTRs对CD47蛋白表达和局部化的影响.
- 研究了RNA结合蛋白HuR (ELAVL1) 和SET在调解3' UTR依赖蛋白转位中的作用.
- 研究了不同CD47 3' UTR异型的功能后果.
主要成果:
- CD47的长3' UTR促进细胞表面表达,而短3' UTR将蛋白质准到内质网膜.
- 一个涉及HuR和SET的复合体,由长CD47 3' UTR招募,通过RAC1.1促进转化后转移到血膜.
- 不同的CD47的3' UTR异型导致不同的蛋白质功能.
- 其他HuR结合基因 (CD44,ITGA1,TNFRSF13C) 的长3' UTRs也增强了表面蛋白质的表达.
结论:
- 替代3' UTRs作为膜蛋白定位和功能的关键调节者,独立于RNA定位.
- 3' UTRs可以在翻译过程中充当支架,招募蛋白质复合体来指导新生的蛋白质运输和功能.
- 3' UTRs的ApA介导调节代表了产生蛋白质组功能多样性的广泛机制.
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